#include<stdio.h>
#include<string.h>
int main(){
	int i,j,length;
	char a[81];
	printf("Please input a array:");
	gets (a);
	length=strlen(a);
	for (i=0,j=length-i-1;i<j && a[i]==a[j];i++,j--);
	if (i>=j)
		printf("YES\n");
	else printf ("NO\n");
	return 0;
}